TdF surprises/observations through 4 stages (Spoiler Alert)

Observations:
1. The importance of overall team strength has never been so apparent to me
2. Velonews prediction of an all Astana podium doesn't seem so crazy now
3. This is a climbers tour, so a lot can change for Evans, Schlecks, Sastre...but how can they make up time on AC in the mountains?

At this point of the race, I'm not surprised by the things on your list - although I thought Levi would be the top positioned rider on Astana after the two time trials. One thing you've overlooked - Astana have a legitimate contender for Lanterne Rouge too.

Observations:
1. The importance of overall team strength has never been so apparent to me
2. Velonews prediction of an all Astana podium doesn't seem so crazy now
3. This is a climbers tour, so a lot can change for Evans, Schlecks, Sastre...but how can they make up time on AC in the mountains?